Biographical material includes the draft of Mourant's autobiography, Blood and Stones published after his death in 1995, together with the correspondence and papers Mourant assembled while writing it. There is also documentation of Mourant's education at Victoria College Jersey and at Exeter College Oxford. The latter includes notes on lectures 1922 - ca 1926. Documentation of Mourant's career, honours and awards is patchy, although there is material relating to his search for employment in the early 1930s. There are pocket diaries spanning 1915-1982, with a fairly continuous sequence 1922-1961. Biographical material also includes extensive family and personal correspondence, much of which dates from or relates to the German occupation of Jersey or shortly thereafter. Mourant's other documented interests include his membership of the Methodist Church and his political affiliations, the League of Nations Union in particular.

There is a little material relating to Mourant's early career with the Geological Survey 1929-1931, miscellaneous material relating to Mourant's service with the MRC's Blood Group Reference Laboratory at the Lister Institute and the Nuffield (later Anthropological) Blood Group Centre at the Royal Anthropological Institute, London, and more extensive but uneven coverage of the Serological Population Genetics Laboratory. Although there is some documentation of the foundation of the Laboratory 1964-1965 and of its staff, the surviving material consists chiefly of correspondence and papers relating to Mourant's largely successful efforts to find continued funding for the Laboratory 1969-1977. Haematological research material, though not extensive, covers Mourant's work in a number of areas from research on blood serum in the mid-1940s to the mapping of blood groups in the 1960s and 1970s. There are early research notes, correspondence and papers relating to student and other expeditions undertaking blood group and physical anthropology research and some MRC material assembled by Mourant relating to projects in which he had an interest. The largest group of research papers, however, is maps and data produced during preparation of the second edition of The Distribution of the Human Blood Groups. There is a chronological sequence of drafts and correspondence relating to Mourant's publications, 1929-1991, with extensive material relating to editions of The Distribution of the Human Blood Groups and to The Genetics of the Jews (1978). There is also editorial correspondence relating to publishers and journals, chiefly invitations to review books or referee papers and an incomplete set of offprints. There is correspondence and papers relating to some of Mourant's lectures and broadcasts, most notably the lectures on blood groups given at the Collège de France, Toulouse, 1978-1979. Societies and organisations material is not extensive, and is confined to brief documentation of only a few of the societies and organisations with which Mourant was associated. It includes professional and geological bodies as well as haematological, biological and medical organisations. Visits and conferences material covers the period 1960-1987. It is not comprehensive, though there is also considerable documentation of Mourant's visits and conferences in the papers he assembled in the course of preparing his biography and with lectures material. Mourant's correspondence is extensive. Its complexity reflects Mourant's organisation of the material, the bulk of which was found in three main series: 'Foreign 1965-1977', 'Biological' and 'Geological', together with a fragment of a fourth series 'Home 1965-1977'. Principal correspondents include C.C. Blackwell, B. Bonné, O.J. Brendemoen, V.A. Clarke, L.L. Cavalli-Sforza, A. W. Eriksson, T.J. Greenwalt, J.K. Moor-Jankowski, T. Jenkins, W.S. Pollitzer, D.F. Roberts, J. Ruffié, D. Tills and J.S. Weiner.

The records cover the period 1927-1993, although the majority date from the 1940s to the 1970s. Notable series include general correspondence with colleagues world-wide, 1935-1984; Dr Race's research papers on human genetic markers, late 1930s/early 1940s; files of correspondence, research notes, pedigrees etc. on blood grouping investigations, 1942-1993; and a comprehensive collection of photographs recording Medical Research Council Blood Group Unit staff at work and play, 1927-[1980s].

Papers of Lionel Sharples Penrose, 1806-1974, comprising personal papers relating to Penrose and his family, 1806-1974; papers relating to the professional training, medical, scientific and voluntary work of Penrose, 1918-1972; letters, mainly to Penrose, 1915-1973.